Q1: the Earth’s surface also absorbs a large amount of energy from the atmosphere

Qn 2: The quote is not justified and it’s meant to make fun of people who are ignorant about global warming and don’t know the difference between weather and climate.
The difference between weather and climate is the measure of time. Climate describes the typical and average weather a region will have over long period of time, like 30 years or more. This is why scientists use climate for statistics about earth’s temperature and whether it’s getting warmer or colder. Weather on the other hand isn’t reliable and it’s nothing more than the condition of the atmosphere over a short period of time.

Qn 3: due to the specific microwave radiation that trigger rotation of water molecules, water molecules from the atmosphere absorbed the microwave radiation as well and interfered w the detection of intended objects

Q4. Air quality is the most serious problem for us in the short run as it is the most tangible, i.e. we can actually feel how unhealthy the air is for us when we breathe.
Global warming is the ‘silent killer’ that is the most serious in the long run, as it raises temperatures gradually and, in time, will make life on Earth unliveable.